.app {  
    perspective: 1500px;
    width:200px;   
    height:200px;   
    position: relative;  
    margin: 100px auto;   
    transform-style: preserve-3d;   
    transform: rotateX(-14deg) rotateY(-45deg); 
}       
.common {   
    position: absolute;   
    top: 0;   
    left: 0;   
    width: 200px;   
    height: 200px;   
    background:#666;   
    opacity: 0.8;   
    font-size:20px;   
    text-align: center;   
    line-height:200px;   
    font-weight: bold;   
    color:#fff;   
    border:1px solid #fff;   
}       
.right {   
    transform: rotateY(180deg) translateZ(101px);
    background: rosybrown;

}    
.left {   
    transform: rotateY(-90deg) translateZ(101px);
    background: rosybrown;
}          
.bottom {   
    transform: rotateX(90deg) translateZ(-100px);
}   
